Digital image products are typically able to perform multiple tasks. For example, digital versatile disk (DVD) players are not only able to play back DVDs but also music compact disks, video CDs, and MP3 audio. In order to remain competitive, digital video player manufacturers must continue to add new and innovative features to their players without increasing the price of the product. In some cases, the manufacturers must add these features while reducing the product price.
One of the more important new features is the ability to play back compressed digital still image files on a DVD player. These still images may have been created by digital cameras, photo scanners, or other digitizing means and then stored on a DVD, CD, or any other type of digital data storage media.
Most DVD players are comprised of two processing functions. One is the programmable central processing unit (CPU) that handles general control of the player. The second function is a hardwired engine that handles Moving Picture Expert Group (MPEG) decoding and displaying processes. As is well known in the art, MPEG is a video compression standard.
Still digital images are compressed using a different standard from MPEG. One example of such a compression standard is Joint Photographic Experts Group (JPEG). Typically, still digital image compression standards are not compatible with MPEG. Therefore, DVD CPUs/MPEG processors cannot support the display of digital still images.
One solution to this incompatibility is to add a still image processor (e.g., JPEG decoder) alongside the existing DVD MPEG processor. This approach, however, increases the cost of the DVD player.
Another solution is to shut off the DVD MPEG processor and load the CPU with still image decoding software codecs. This approach relies on the CPU alone to perform the still image decoding and display tasks. This approach is not commercially feasible due to the heavy task of image decoding performed by the CPU. The CPU takes a large amount of time to decode and display a still image. There is therefore a need in the art for an apparatus that economically displays both digital video and digital still images.